Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

Objective To investigate the status of hearing impaired children's hearing device independence skills,and to explore the ways to improve their self-use of hearing equipment.Methods This study surveyed 64 re-habilitation teachers and 411 parents of children with hearing impairment aged 0-12 years.Through face-to-face or remote telephone interview,3 good habits(A asking parents for advice before removing the HA,B putting the de-vice into a moisture-proof box after removing it,C bringing batteries to school and knowing where are them)and 3 key abilities[D wearing the device independently,E replacing the battery independently,and F independently handle foreign bodies in the ear mold(Fa)and water vapor(Fb)]was investigated.The age when mastering skills or de-veloping habits difference of hearing impaired children in different groups were compared.Results ① The ratio of ability D in the bilateral CI group and the bilateral HA group of preschool children was 30.97％and 18.57％respec-tively.Among elementary school children,85.29％and 90.70％had this ability respectively.② The ratio of ability E in the bilateral CI group,the bilateral HA group and the bimodel group were 11.50％,15.71％and 16.49％,re-spectively.Among elementary school children,64.71％,53.49％and 68.52％had this ability,respectively.③Among preschool children,there was no statistical difference in age when different equipment groups developed the three good habits and acquired ability D and E(P＞0.05).④ Among primary school children,there was a statisti-cal difference in the age when different equipment groups formed habit A(P＜0.05),and the age when double CI group had this ability was slightly earlier than the double HA group.There was no significant difference in other abilities among age groups(P＞0.05).Conclusion The age at which hearing impaired children develop the three good habits precedes the age at which they master the key skills,which accords with the law of skill acquisition and development of ordinary children.Corresponding teaching process should be based on the age and ability of hearing-impaired children without considering the type of equipment.

Sufficient keratinized mucosa is important for ensuring the long-term stability and aesthetics of dental implants.How to ef-fectively augment the soft tissue volume at sites with insufficient keratinized mucosa width(KMW)has gradually become a hot research topic for current scholars.Apically positioned flap(APF)with free gingival graft(FGG)is recognized as the approach of choice for peri-implant keratinized mucosal augmentation,but the postoperative shrinkage and its influencing factors are not completely clear.The objective of this review is to explain the significance of keratinized mucosa to peri-implant tissue health,analyze the relevant factors af-fecting postoperative contraction of free gingival grafts,and finally propose a risk factor assessment table for postoperative shrinkage of FGG,with the aim of providing clinicians with a scientific and effective strategy for peri-implant soft tissue management.

Objective To explore the effects of the disinfection port position and diameter and disinfectant concentration on the in-situ decontamination of the flow field-based biosafety high efficiency particulate air filter device with the computational fluid dynamics(CFD)method.Methods ANSYS DesignModeler was used to construct five models for the high efficiency particulate air filter device with the disinfection port at the side end in four ones and upper end in the remained one model,with the diameter being 70,100,150,260 and 260 mm respectively;secondly,a standard k-ε turbulence model was applied to simulating the velocity field and concentration field inside the high efficiency particulate air filter device,so as to analyze the influence of the vortex position inside the device and the structure of the device on the disinfection effect and to determine the optimal structure of the device;finally,H2O2 with the concentration of 0.45,0.35 or 0.30 mol/L was selected as the disinectant to investigate the effect of the disinfectant concentration on the disinfection under the optimal device structure.Results Simulation showed that there were vortexes existed the cavity between the filter compression structure and the filter of the high efficiency particulate air filter device.The disinfection effect in case of the disinfection port at the side end was higher than that in case of the disinfection port at the upper end;the diameter of the disinfection port had influences on the disinfection effect,and high-concentration disinfectant was found in the device when the diameter was 100 mm.The optimal structure with the disinfection port at the side end and the diameter of 100 mm was determined for the high efficiency particulate air filter device.An increase in H2O2 concentration was beneficial to improve disinfection without corroding and damaging the device when the in-situ decontamination of the flow field-based biosafety high efficiency particulate air filter device was carried out.Conclusion The characteristics of the internal flow field of the flow field-based biosafety high efficiency particulate air filter device and the influencing factors of the in-situ disinfection effect are revealed,and theoretical references are provided for the optimal design of the device.[Chinese Medical Equipment Journal,2025,46(9):22-27]

Objective To construct a competency evaluation model for forensic practitioners,providing a reference for their training and assessment.Methods Based on the iceberg and onion models of com-petency,and with reference to Spencer's Competency Dictionary,literature research was conducted and focus group interviews were employed to preliminarily construct core indices and measurement items for evaluating the competency of forensic practitioners.The Delphi method was applied for two rounds of expert consultation to further refine the competency evaluation index system.The analytic hierarchy process(AHP)was used to calculate the weights of the indices.Results A competency evaluation model for forensic practitioners was constructed,consisting of 7 core indices,encompassing forensic skills,identification service capabilities,and the ability to apply relevant legal knowledge and 49 mea-surement items.The weights of the core indices and measurement items were determined.Conclusion The constructed competency evaluation model for forensic practitioners is scientifically sound and inno-vative,and has unique characteristics of forensic medicine compared with other medical models.

Hilar cholangiocarcinoma is insidious in onset and often causes obstructive jaundice due to bile stasis,leading to impaired liver function.For tumors with malignant obstructive jaundice,biliary drainage is often performed before surgery in clinical practice.Currently,the commonly used drainage methods are percutaneous transhepatic biliary drainage(PTBD)and endoscopic retrograde biliary drain-age(ERBD),but there are controversies over the advantages and disadvantages of the two drainage methods.PTBD drainage can often lead to tumor implantation metastasis,but the underlying mechanism remains unclear.We detected tumor cells in PTBD and ERBD bile samples from hilar cholangiocarcino-ma patients,subsequently explored their tumorigenicity and mechanisms through tumorsphere assay in vitro and xenograft tumor models in vivo.The experiments included benign gallstones group(30 cases)as a negative control,PTBD group(14 cases)and ERBD group(13 cases).Tumorsphere formation was i-dentified in 3 cases(23％)among the 13 cases of ERBD group,in 6 cases(42％)among the 14 cases of PTBD group,but there were no tumor cells or formed tumorspheres in the 30 cases of benign gallstone group.The tumor sphere formation ability of cells in the PTBD group was significantly higher than that in ERBD group.Subcutaneous xenograft tumor assays showed that tumor growth in the PTBD group was sig-nificantly higher than that in the ERBD group.Tumor cells in PTBD bile possessed stronger tumorigenici-ty compared with the ERBD group.Mechanically,stem cell transcription factor Nanog mRNA levels were significantly higher in the PTBD group compared to the ERBD group.Both tumorsphere formation and xenograft tumor growth were reduced by Nanog knockdown in three cases of the PTBD group,indicating the important roles of Nanog in tumorigenicity of PTBD group tumor cells.The half-life of Nanog mRNA was longer in PTBD group cells than in ERBD group cells,suggesting potential post-transcriptional regu-lation on Nanog mRNA.The Nanog m6A level was higher in PTBD group tumor cells compared to the ERBD group.Analysis of methyltransferases and demethylases,ALKBH5(α-ketoglutarate dependent dioxygenase alkb family homolog 5)mRNA levels were lower in the PTBD group than in the ERBD group and significantly correlated with the m6A level of Nanog.ALKBH5 knockdown led to an increase in the m6A level of Nanog,while ALKBH5 overexpression decreased the m6A level of Nanog.Dual-luciferase activity assays demonstrated that ALKBH5 knockdown significantly enhanced luciferase activity,whereas ALKBH5 overexpression reduced it.Further studies confirmed that ALKBH5 knockdown upregulated both the mRNA and protein levels of Nanog,whereas overexpressing ALKBH5 downregulated them.ALKBH5 mediated the demethylation modification of Nanog mRNA,and the lower levels of ALKBH5 expression in the PTBD group promoted Nanog's m6A modification.Overexpressing ALKBH5 decreased tumorsphere growth,while ALKBH5 knockdown increased it,which was subsequently reduced by the simultaneous Nanog knockdown again.In sum,tumor cells in PTBD and ERBD drainage bile from hilar cholangiocar-cinoma patients exhibited tumorigenicity.Compared to the ERBD group,tumor cells in PTBD bile with lower ALKBH5 expression levels enhanced Nanog's m6A modification to upregulate Nanog expression levels,resulting in stronger tumorigenicity.These findings are significant for elucidating propensity to tumor implantation metastasis from PTBD drainage.

Objective:To compare minimally invasive surgery with traditional open surgery, analyze the current application status of health economic evaluations in the treatment of digestive tract cancers, such as esophageal cancer, gastric cancer, and colorectal cancer by minimally invasive surgery and provide evidence for the rational selection of clinical treatment, alleviation of disease-related economic burdens, and rational allocation of healthcare resources.Methods:By using five databases, i.e. China National Knowledge Infrastructure, Wanfang data, Chinese Biomedical Literature Database, PubMed, and Embase, a database was established to retrieve all the papers about health economic studies of minimally invasive surgery for esophageal cancer, gastric cancer, and colorectal cancer published until December 31, 2023. Literature was analyzed by using software NoteExpress 3.8, and data were processed using Excel 2021. The quality of included papers was evaluated using the CHEERS 2022 checklist, and Meta-analysis was conducted by using software Stata 17.0.Results:A total of 10 919 relevant papers were retrieved, and 59 studies were included. Only 14 studies (23.7%) used standard health economic evaluation methods. Meta-analysis results revealed no significant differences in direct medical expenditure and total expenditure between minimally invasive surgery and open surgery. However, the expenditure for minimally invasive surgery exhibited a significant increase [mean difference ( MD)=5 973.12 yuan, P<0.001], while hospital stay and indirect expenditure significantly decreased ( MD: -4.85 days and -733.79 yuan, P<0.001). In China, for gastric cancer, the direct medical expenditure of endoscopic surgery was lower than that of open surgery ( MD=-33 000.00 yuan) with no significant difference ( P<0.001). In colorectal cancer cases, the direct medical and surgical expenditures for laparoscopic surgery were higher than those for open surgery ( MD: 4 277.94 yuan and 4 267.80 yuan, P<0.001), while the indirect and total medical expenditures decreased ( MD: -768.34 yuan and -159.10 yuan). Hospital stays in patients who had minimally invasive surgery for all three types of cancer were shorter than those who had open surgery ( P<0.001). Conclusions:In the treatment of gastrointestinal cancer, compared with open surgery, minimally invasive surgery shows higher expenditure, but has advantages, such as shorter hospital stay and lower indirect expenditure, and there were no significant differences in direct medical and total expenditures between the two approaches. When conducting health economic evaluation, factors such as postoperative complications, hospital stay, and patient's economic status should be considered for their impact on total medical expenditure. It is necessary to pay attention to the application of health economic evaluations in healthcare decision-making.

Objective:To compare minimally invasive surgery with traditional open surgery, analyze the current application status of health economic evaluations in the treatment of digestive tract cancers, such as esophageal cancer, gastric cancer, and colorectal cancer by minimally invasive surgery and provide evidence for the rational selection of clinical treatment, alleviation of disease-related economic burdens, and rational allocation of healthcare resources.Methods:By using five databases, i.e. China National Knowledge Infrastructure, Wanfang data, Chinese Biomedical Literature Database, PubMed, and Embase, a database was established to retrieve all the papers about health economic studies of minimally invasive surgery for esophageal cancer, gastric cancer, and colorectal cancer published until December 31, 2023. Literature was analyzed by using software NoteExpress 3.8, and data were processed using Excel 2021. The quality of included papers was evaluated using the CHEERS 2022 checklist, and Meta-analysis was conducted by using software Stata 17.0.Results:A total of 10 919 relevant papers were retrieved, and 59 studies were included. Only 14 studies (23.7%) used standard health economic evaluation methods. Meta-analysis results revealed no significant differences in direct medical expenditure and total expenditure between minimally invasive surgery and open surgery. However, the expenditure for minimally invasive surgery exhibited a significant increase [mean difference ( MD)=5 973.12 yuan, P<0.001], while hospital stay and indirect expenditure significantly decreased ( MD: -4.85 days and -733.79 yuan, P<0.001). In China, for gastric cancer, the direct medical expenditure of endoscopic surgery was lower than that of open surgery ( MD=-33 000.00 yuan) with no significant difference ( P<0.001). In colorectal cancer cases, the direct medical and surgical expenditures for laparoscopic surgery were higher than those for open surgery ( MD: 4 277.94 yuan and 4 267.80 yuan, P<0.001), while the indirect and total medical expenditures decreased ( MD: -768.34 yuan and -159.10 yuan). Hospital stays in patients who had minimally invasive surgery for all three types of cancer were shorter than those who had open surgery ( P<0.001). Conclusions:In the treatment of gastrointestinal cancer, compared with open surgery, minimally invasive surgery shows higher expenditure, but has advantages, such as shorter hospital stay and lower indirect expenditure, and there were no significant differences in direct medical and total expenditures between the two approaches. When conducting health economic evaluation, factors such as postoperative complications, hospital stay, and patient's economic status should be considered for their impact on total medical expenditure. It is necessary to pay attention to the application of health economic evaluations in healthcare decision-making.

Objective To explore the validity and feasibility of the left transthoracic and esophageal hiatal approach for Siewert type Ⅱ adenocarcinoma of the esophagogastric junction under a single position.Methods The clinical data of 64 patients with Siewert type Ⅱ AEG(single position transthoracic approach group)treated with the left transthoracic and esophageal hiatal approach under a single position and 56 patients with the laparoscopic transesophageal slit approach(transabdominal approach group)in the Department of Thoracic Surgery,Huaihe Hospital of Henan University,from January 2017 to December 2018 were retrospectively analyzed.The clinical and pathological data,perioperative indicators(operation time,intraoperative blood loss,postoperative first ambulation time,postoperative first peristalsis time,postoperative drainage volume at 3 d,incidence of postoperative complications,postoperative hospital stay),postoperative complications(positive surgical margin,proximal esophageal resection margin,tumor diameter,total number of dissected lymph nodes,positive lymph node dissection rate,postoperative histopathology,and TNM staging of tumor pathology),and survival indicators(tumor recurrence and metastasis rate and survival at 1 month,3 months,6 months,1 year,3 years,5 years after surgery)were compared between the two groups.Kaplan-Meier method was used to analyze the postoperative survival rate of the two groups.Univariate analysis using χ2 test was employed to analyze factors influencing 5-year postoperative survival rate in Siewert type Ⅱ AEG patients.Results No significant difference was observed in clinical and pathological data,such as gender,age,American Society of Anesthesiologists(ASA)grade,tumor differentiation,pTNM stage,and tumor diameter between the two groups(P>0.05).No significant differences were noted in intraoperative blood loss,incidence of postoperative complications,and survival rates at 1 month,3 months,6 months,1 year,and 3 years after surgery between the two groups(P>0.05).The single position transthoracic approach group exhibited a higher postoperative drainage volume at 3 d compared to the transabdominal approach group(P<0.001),a shorter surgical time(P<0.001),a longer time to first mobilization,first intestinal peristalsis,and hospital stay after surgery(P<0.01),a longer proximal esophageal margin(P<0.001),a higher total number of lymph node dissections(P<0.001),and a higher positive lymph node dissection rate(P<0.05)than the transabdominal approach group.The 5-year recurrence-free survival rate of the single position transthoracic approach group was higher than that of the transabdominal approach group,with a statistically significant difference(P=0.013).The Kaplan-Meier survival curve showed no statistically significant difference in the 5-year overall survival rate between the two groups of patients after surgery(P=0.456).The results of univariate analysis indicated that there are significant relationships between tumor differentiation degree,pTNM stage,tumor diameter,and lymph node positivity rate with the 5-year postoperative survival rate in Siewert type Ⅱ AEG patients(P<0.05).Conclusion Siewert type Ⅱ AEG patients can be treated with the left transthoracic and esophageal hiatal approach under a single position,achieving the same effect as laparoscopic transesophageal slit approach,and it can be actively promoted as a complementary choice of operation in the clinic.